Telegraph signal circuits



R. P. MOORE TELEGRAPH SIGNAL CIRCUITS Filed March 11, 1922 IN VEN TOR. A. 1. (WW BY g Patented Jan. 20, 1925.

ITED

ROBERT P. MOORE, or

snares PATENT @Fidlfi DAYTON, nnu'ruciiv, Les-station iro Mancini "TELEPHONE AND TELEGRAPH COMPANY, A CORPORATION 033 NEW YORK.

mnnnennrn SIGNAL crncurrs.

Application filegilviarch 11, 1922. Serial No. 543,105.

This arrangement relates to. telegraph -systems and consists in providing means whereby the attendant at the 'telegraph board may automatically be signaled whenever the telegraph circuit is left' ope n an undesirable length of time. ltis frequently necessary for telegraph operators .to leave a key open for the purpose of keeping control of a circuit under certain imperative conditions. Such anopening .of the key would operate thesigi'ialing device at the telegraphboard. Accordingly it will be seen that should thekey be left open when no actual fault existed on the circuit that.

- it would cause confusion andwould unnecessarily delay the. service. The arrangements of this. invention will signal the operator at 1 1 the telegraph board whenever the key is left open :longer than the usual length of time so that the cause therefor may be investigated. However, the signallng arrange ments will not operateor be afiectedby the Y, invention.

usual openings or closing ofthe key utilized for normal signaling purposes. With the arrangements of the invention it may be 'ing means fora time interval of over a minute after the opening of the telegraph circuit. The arrangements of the invention may be more fully understood fromthe detailed description :liereinafter given.

The invention may be more fully understood from a. consideration of the accompanying drawing, in which is shown a circuit diagram oflthe arrangements of the At the telegraph board there are usually provideda number of jacks, which are herein shown as jacks J ,,.J J

J J J,, .L, and J Jack J is used for.

supervisory purposes. l Jacks J J .L, and J 5 may be utilized for interchanging lines, loops and telegraph equipment. The jacks J J and J 8 may be used for establishing connections with subscribers loops, such as possible-to delay the operation of the signalthe loop L which includes the sounder S, the telegraph key K and the auxiliary key K,. A telegraph line L is shown associated with the telegraph board. A signal device, such as lamp 31, is also providedat the telegraph board. The relay arrangements of the invention are so associated with the telegraph board that they will control the signallamp 31 so'that it will operate whenever the telegraph circuit L is left open an undesirable length of time, but it will not operate upon the normal openings of the line L utilizedfor transmitting message signals. The relay arrangements of the invention consist of the relay 2, which is slow-releasing but quick operating,the difl erentially wound relay 13, whose parallel circuits include the resistance 16 and the ballistic resistance 17, the differential relay 5, and the signal controlling relay '23, which will be described in detail hereinafter.

The operation of the arrangements of the invention is as follows: The telegraph connection with one of. the local loop circuits, such as the loop L is as follows: from the telegraph line L, contacts of jacks J and J conductor 1, winding of relay 2, conductor 3, contact jack 5,, conductor at. left-hand winding of relay 5, conductor 6, contacts of jack J and plug P over the loop circuit L to the contacts of the. plug P and and jack J and the contacts of jacks J and conductor 7, right-hand winding of relay 5, conductor 8, contacts "of jacks J and 5,, conductor 9 and battery 10 to ground. The openings and closings of the telegraph circuit L or L will operate the sounder S in the local loop circuit. These openings and closings of the telegraph circuit, however, will not operate the relay 5 as it is 'v-Jound diiferentially. The current in the above traced circuit, furthermore, will hold in operated condition the relay which is adjusted to be slow releasing and will not allow its armature to fall off during the normal intervals in which the telegraph circuit l; is open for the purpose of transn'iitting message characters. If the telegraph circuit L now remains left open ionger than the usual period for transmitting message characters, the relay 2 will allow its armature to fall off and close the following circuit: from ground and battery ll, armature and contact of relay 2, coin ductor 12, through the windings of relay 13, which are differentially arranged over the. parallel circuits lt and 15, and over conductor 18, right-hand armature and contact of relay 23, to ground. The parallel circuits 1+ and 15 include the resistance element 16 and the ballistic resistance 17. These resistances are normally equal and accordingly the relay 13 will not operate at once. The ballistic resistance 17, however, will increase upon the current flow theretlnrough and will gradually destroy the condition of equilibrium existing in the differentially arranged windings of relay 12, and accord-g ingly, after an interval, the relay 13 will operate. Upon the operation of relay 12' the following circuit will be closed 1 from ground and battery 19, conductor 20, arrnture and contact of relay 13, conductors 21 and 22, winding of relay 2%), conductors 24L and 25, contact of jack 5,, conductor 26, contact of jack J conductor 27, to ground. The closing of this circuit will operate the relay 23, which will be locked up over the following circuit: from ground and battery 28, left-hand armature and contact of relay 23, conductors 2 and 25, contact of jacl; J,

conductor 26, contact of jack J conductor 27, to ground.-- The operation of relay 23 will close the following circuit through the signal lamp 31: from ground and battery 28, conductor 29, armature and right-hand make contact of relay 23, conductor 30 through the filament of lamp 31 and thence either to ground or to buzzer circuit, not shown, thus operating the lamp 31. The

operation of the lamp 31 under these condi tions will indicate to the repeater man at the telegraph board that the telegraph circuit L has remained open a longer timethan is usual, or that some trouble or ground exists on the line, and he will investigate the cause thereof. In order that the sub-- scriber on the local loop circuit, such as L may signal the repeater man at the telegraph board, the relay 5 is provided and the supplementary key K is provided in the loop circuit. The operation of the key K will close the following circuit: from ground, contact ofkey K contact of plug P and jack J contacts of jacks J, and

J conductor 7, right-hand winding of relay from ground and battery 19, armature and contact of relay 5, conductors L0 and 22, winding of relay 23, conductors 2i and 25, contact of jack J conductor 26, contact of jacltd conductor 27, to ground. The closing of this circuit will operate the relay 23, which, in the same manner as has been pre- \iously pointed out, will cause the operation of the signaling device 31.

With the arrangements of this invention which may beadded to the usual equipment at the telegraph board, the repeater man thereat may be signaled automatically whenever the telegraph circuit remains open more than a desirable length of time, and in order to provide a margin of safety and to insure against false operation of the signaling device, a time interval of as much as sixty seconds or more may easilyibe introduced with the arrangements ofthis invention before the signaling device at, the telegraph board will'operate. H

While the invention has been disclosed in certain specific arrangements which are deemed desirable, it is to be understood that it is capable of embodiment in many and widely varied forms without departing from the spirit of the invention as defined'in the appended claims.

What is claimed is: i

1. A telegraph line terminating ata board a circuit controlled by said relay, a second 7 relay in said circuit, means in said circuit 7 for-retarding the operation of said second relay, and means controlled by saidsecond relay for operating said signaling means.

2. A telegraph line terminating at a board at a central station, a signaling device located at said station, aslow releasing relay located. at said station, the winding of said relay being included in sa1dtelegraph line,

a circuit controlled by said relay, a second relay in said circuit, means in'said circuit for. retarding the operation of said second rel.ay, a-third relay for controlling said signaling device, andmeans controlled by said second relay for controlling said third relay. 3. A telegraph line terminating at a board a central station, a signalingdevice lo cated at said station,a slow releasing relay located at said station, the winding of said relay being included in said telegraph line, and means controlled by the release of said relay for operating said signaling device, said'relay being adjusted so th-atit will releaseronly when saidtelegraph line is left open a longer interval than the normal interval utilized for transmitting message characters. V r

' 4. A telegraph line terminating at a board at a central station, a signaling device located at said station, a slow releasing relay located at said station, the winding of said relay beingin'cluded in said telegraph line and said relay being adjusted so that it will release'only when said telegraph line is left open a longer interval than the normal in terval utilized for transmitting message characters, a second relay, two parallel cir cuits, controlled by said slow release relay,

-' one of said parallel circuits including one of the differential windings of said second relay and a resistance, the other parallel circuit including the other differential winding of said second relay and a ballistic resistance, and means controlled by said second relay for operating said signaling device.

In testimony whereof, I have signed my name to this specification this 9th day of February, 1922.

ROBERT P. MOORE. 

